Dehydrator plug



UCL 2l, 19,52 M. E. CHANDLER Erm.

DEHYDRATOR PLUG Filed Dec. 3, 1947 Patented Oct. 21,

, y DEHYDRATOR PLUG l A Milton E.' Chandler, New Britain, and Scott F. f Hunt, Meriden, Conn., assignors to Nilesement-PondCompany,

'mmfoEFicE "bustionengines 4 plastic materials,=such as 'Ier'liteA (cellulose 4acetate butyrate) in order that the condition'oi 'su'iciently moisture-proof very-smallr permissible absorption of moisturer of the weight of thel ber gasket, for

, 1 Aimaddition to the foregoing,

a corporation of New Jersey Application lleceniber 3, 1947,75

17 Claims. (Cl. 18S-4.8)

Thisinventionfpertainsto dehydrating devices for removingmoisture from 'hermetically sealed `chambers and more particularly has reference to such devices in the form of dehydrator plugs for-use in inhibiting corrosion from moisture vin internal combustion engines while in storage or 'shipment'.` Y 'overthe plastic This'inven'tio'n is an improvement type of dehydrator plug disclosed in UnitedStates lPatent No, 2,406,993,

- September 3,-1946 Heretofore, dehydrator plugs for internal comhave been madeof' transparent the dehydratingmaterial in the plug, as indicate-d by its color, 'could be observed-without disassembling-the plug. However, plastic plugs 'Were' unsatisfactory because no quatetransparency and strength was found to be which must not exceed 2% dehydrating material in the plug when exposed tov an atmosphere of 100 F. temperature and 100% humidityl f f =Various 'expedientsliave been resorted to in Aaneffort to ldevise a dehydrator plug more satisfactory than'those made of plastics, the most y.successful "embodying combination i the use of a glass and metal "plug, in which the main body fof the plug is composed of a metal diecasting hollow glass capthrough and the outer end a which the color of the dehydrating material can be seen. While this form of plug is an improvement over the plastic plug, it is attended with I certain practical diiiiculties and disadvantages, the most serious of which is the diiiiculty and uncertainty 'of obtaining a moisture-tight jointv between the vglass cap and the metal body` of the plug. Attempts to form a satisfactory joint by casting-the metal ofthe body aroundkthe lower anged end of the cap invariably rresulted in vcracking or breaking the cap from heat and pressure and were f-unsuccessful. Crimping a .thin edgej of the die-cast body over the flanged end of the glassfcap also proved factory, since it failed to produce a permanent moisture-'tight joint, even with the use of a rubthe reason that the gasket tended to takel apermanent set and the die-cast crimped i edge did not have sufficientr resiliency to hold the abutting members in moisture-tight contact.y

` it has been found to be exceedingly difficult to prevent a small amount'of porosity in a certain percentage of dieissued to meet the required plasticmaterial of adeimproved West Hartford, Conn.,

rial No. 789,35)

permit excessive permeation of moisture into the interior of the plug from outside atmosphere and-'thus rapidly reduce the -dehydrating material in the plug to a condition' of ineffectiveness. I tis accordingly an object of this invention to overcome the defects and disadvantages of prior art devices and provide a dehydrator plug which fully meets all moisture resistance requirements and which is more economical to manufacture and easy to charge and install in an engine being prepared for storage or transportation.

Another object resides in the provision of an dehydrator plug which may be kept in storage for a prolonged period without appreciable deterioration and which can be rendered operative for installation in an engine by a simple removal of a sealing cap from the end of the plug. Y "A still further object resides in the provision of improved dehydrating materials which are more economical in cost and more efficient in use. l

With these and other objects in View, which may be incidentto our improvementaour invention consists in the combination and arrangement of elements hereinafter describedl and illusf trated in the accompanying drawing inv which as it will be apparent to those skilled in the art more or less unsatisthat various changes in theillustrated constructions may be resorted to without in any way exceeding the scope of theinvention.

In the drawing:

VFigure 1 is apartly elevational View of a dehydrator plug constructed according to the invention and showing the manner in which the spark plug cable of the engine is attached.

Fig. 2 is a bottom plan view of the plug illustrated in Fig. 1.

Referring to the drawing in detail, the reference numeral iindicates the body of the plug which is formed of non-corrosive sheet metal-in the `specific novel manner hereinafter described.

Bythe use of sheet metal instead of a` die cast- 1 'ing to form the body of the dehydrator plug, we secure several material advantages.

Vmetal, being' of dense uniform texture, is free Sheet of small pores which are inherent in die castings and thus prevents leakage of moisture through porosity of the metal. Also the sheet metal body vsectional and partly side' 3 is less expensive to vfabricate and lighter in weight than a corresponding die casting which reduces the cost of manufacture and transportation of the dehydrator plug.

The upper portion of the plug consists of a transparent glass cap 2, having a central cavity 3 for the receptionof a portion 4 of the dehydrating material, and an outwardly extending integral ange 5 on which is seated a resilient gasket 6 of rubber or similar material.v This gasket is tightly -embraced by a flange 1, forming the upper .end

f the body member I, which is crimped over gasket 6 after cap 2 is assembled to the V.body I, las clearly shown in the drawing. Theupper endof cap 2 is formed in the shape of a knob 8 with a reduced neck portion 9 and an undercut bead l o adapted to engage a similar bead II on the lower end of a resilient sleeve I 2 which is provided with threads I3 for the engagement of a sleeve nut on the end of the spark plug terminal (not shown) The sleeve I2 lis shown fin dotted lines inthe drawing as it forms no part of this inventionand is included in the drawing merely to illustrateone way in'which the spark plug cable may be attached to our improved dehydrator plug. 'It is obvious thatotherrneans may be employed to attach the terminalof the spark plug cable to the end of the dehydrator plug.

The metal ywall of body I `just below flange 'i is folded in to form a ange seat I5 :for the lower edge of cap 2 andgasket 6, so that when flange 'I is crimped over gasket 6 it holds the saidgasket and cap firmly against seat 1M, thus forming a moisture-tight joint between cap y2 and body i. Moreover, since the sheet metal composing body I has considerable resiliency, it embraces gasket 6 .with a resilient grip which if, vafter a time, the gasket tends to take a permanent set, it will still be pressed rmly against flange 5 of cap 2 and seat I4 of body lI so as to continue to maintain a moisture-tight Yjoint therebetween. By lthis novel means we have overcome one ofthe most important defects of prior art devices wherein it was sought to attach a glass cap to a (die-cast.) metal body with a permanent moisture-tight joint, but without success, because of the unyielding nature .of the metal in the die-cast body.

It will be noted that the lower outeredge of flange 5 is chamfered to form abevelededge i5 so that the lower end of cap 2 actually contacts seat I4 of body I in a single line, instead of an-annular area of material width. In this Way, themajorityof the force `holding cap 2 against body I is exerted through gasket 6. Also vthe line of contact betweencap 2 and seat I 4 is near the inner edge of said seat and since this seat is formed from the resilient metal of body Iit tends to yield to any localized pressure from the lower end of cap 2, so that ifa bending force or accidental blow is applied to cap 2, the resulting stress is absorbed by gasket 5 and resilient seat I4, thus preventing spalling of the lower outer edge-of cap 2 or breaking of the cap.

Near its lower end, body I is pressed in to form an annular inwardly-projecting rib If which serves as a seat for circular discs I 7 of filter paper and ywire mesh screen I8. After assembling against rib l5, discs I7 and I8 are held securely in position by crimping the bottom edge of body I to form an inwardly projecting ilangeY I9, as clearly shown in Fig. l.

The upper portion of body I, below .fiange I4, is pressed intoa polygonal shapev so as to vprovide a plurality of at surfaces 20 for the application of a wrench. Below its polygonal portion, body I is'pressed in to form a shoulder 2I which serves as a'seat for a gasket 22, below which body I is provided with a threaded portion 23 for engagement with a similar threaded portion 24 of a sheet metal sealing cap 25. When cap 25 is threaded into body I so that its flaired upper edge 2B rmly engages gasket 22, a moisture-tight `joint is formed between cap 25 and body I. Sealing cap 25 is applied to body I during storage and transit of the dehydrator plug and is removed just before the Vplug is applied to an engine cylinder.

For dehydration purposes, We have found that silicia gel is by far'the most suitable material, as it never becomes progressively moist in a humid .atmosphere'and the moisture which it adsorbs from the surrounding atmosphere can only be driven off by the application of heat to a degree far above that ever attained by nature. Silica gel may be treated .with certain salts, such as an iodine or cobalt salt, which gives it a distinctive color, such as deep blue, when dry, and which color gradually changes to another distinctive color, such as pale pink, when saturated with moisture. A visual indication ris thus afforded of the state of saturation-of the silicaxgel so that it can be replaced with Vfresh, dry material before it is completely saturated. The use of '.silicagel thusfchemicallytreated for dehydration purposes is old in the art 'and we do notclaim its 4use ex cept in combination with other'novel features of this invention. However, wer have found `that when silica gel is treated as indicated -it -loses some of vits moisture adsorptive powerzand is, moreover, more expensive than untreated Vsilica gel. We `have therefore devised the following* novel and -improved means of using silica gel as adehydration material lin-this invention. Inithe glass cap portion of our dehydrator plug we place chemically treated silica gel 4 containinganxoisture-control indicator which can -be readily observed through the transparentrwall of therrcap, while the main body of the plug is lled with untreated silica gel 21, which is more moisture adsorbent and less expensive than lthe Ytreated silica gel. By this arrangement we have found that the color of the treated gel inthe glass .cap is a satisfactory indication of the `moisture-content condition of both the treated and untreated gel. We thus increase the moisture adsorbent capacity and reduce the cost of the whole silicagel content of the dehydrator plug -by usi-ng only a minor portion of treated gel. A

Substances of the silica gel type 'have'the disadvantage that, being extremely hard, dust formed through attrition mayv damage theparts which the dehydrator plug is intended to protect. Therefore, in order to 4prevent the escape of v:such dust from the dehydrator plug, the filter paper I1 andwire mesh screen Ill are provided to close the bottom of plug against the passage of solidgparticles while affording-free passage; to moisture and water vapor. f

While a suitable mechanicalV arrangement of the invention has been hereinabovev described and illustrated, it `is to be understood/that ythe invention is not to be limited to theparticular form so-disclosed,-but such changes in the-size, shape and arrangement of the various parts and of the materialsv thereof may be resorted to-without departing yfrom the spirit `of this invention or exceeding the scope of the appended-claims.

What we claim as now and desire tosecure by Letters Patent is as follows: i

1. A dehydrating device comprising 'dehydrating material contained in a seamless resilient metal tubular body connected toa substantially hollow, transparent, moisture-impervious cap hermetically and yieldably sealed to one end of said body by deforming said end of said body over a yieldable vgasket surrounding the connecting end of said cap.

2. A device as set forth in claim 1 having a resilient, permanently moisture-tight joint between said body and cap which permits limited relative movement of said body and cap.

3. A device as set forth in claim 2, in which said body and cap each provide a substantial chamber for dehydrating material.

4. A device as set forth in claim 3, in which said body is formed of a single, unitary piece of noncorrosive sheet metal without joints or seams.

5. A device as set forth in claim 4, in which said cap is formed of a single, unitary piece of glass.

6. A device as set forth in claim 1 having a y dust-imperforate but moisture-perforate closure for the end of said body opposite said cap. f

7. A dehydrating device comprisinga hollow, opaque body and a hollow, transparent cap each of which form a substantial chamber for ydehydrating materials, dehydrating material in said body which does not change its color with adsorption of moisture, and dehydrating material in said cap which changes its color with adsorption of moisture, whereby the deterioration of said dehydrating material upon absorption of moisture can be observed through the walls of said cap. v

8. A device according to claim 7, in which the color-changing portion is a minor fraction of the total dehydrating material but sufcient to indicate the moisture content of all the dehydrating material in said chamber. y n

9. A device for dehydrating the air in an engine cylinder comprising dehydrating material in' a seamless resilient metal, tubular body connected to a substantially hollow, transparent, moistureimpervious cap hermetically and yieldably sealed to one end of said body by deforming said end of said body over a yieldable gasket surrounding the connecting end of said cap, means connecting said body to said cylinder and means on said cap for connecting an ignition cable terminal.

10. A device according to claim 9 having a resilient, permanently moisture-tight joint besaid body over a yieldable gasket surrounding the engagement in said tween said body and cap.

11. A device according to claim 9, in which said body is formed of a single, unitary piece of noncorrosive, seamless sheet metal.

12. A device according to claim 9, cap is made of a single, unitary piece of glass.

13. In av device as set forth in claim 9, a unitary, tubular body formed by drawing and stamping a flat piece of seamless resilient sheet metal.

14. A device for dehydrating the air in an engine cylinder and for supporting an ignition cable terminal comprising a seamless resilient metal tubular body connected to a substantially hollow, transparent glass cap hermetically sealed to one end of said body by deforming said end of connecting end of said cap, and a dust-imperiorate but moisture-perforate closure for the other end of. said body.

15. A device according to claim 14, in which said body and cap are filled with dehydrating material.

16. A device according to claim 14, in which said body is adapted for insertion in a spark plug aperture in said cylinder.

17. A device according to claim 14,`in which said body is provided with screw threads adapted to engage the threads in a spark plug hcle'in said cylinder andv hold said device in moisture-tight cylinder.

MILTON E. CHANDLER.`

SCOTT F. HUNT.

REFERENCES CITED The following references are of record in the f file of this patent:

UNITED STATES PATENTS in which said 

